Molokai–Tsunami and Tsunshine

It was at about 7:15pm on Saturday, October 28, 2012, when we saw the first notice that there was a tsunami warning in effect for all of the Hawaiian islands. A couple of hours earlier there had been an earthquake off the coast of British Columbia, Canada, measured at a magnitude of 7.7. Initially, it was thought that this would pose no threat of Tsunami to Hawaii. However, subsequent readings from various measurement buoys convinced the scientists at the Pacific Tsunami Warning Center of a certainty for a Tsunami reaching Hawaii which resulted in them issuing a tsunami warning for the islands. They expected the initial surge to reach the north side of the islands at 10:28pm with possible wave heights 5 feet above normal sea level in Maui.

Let’s evaluate our situation. Our condo is about 100 feet from the ocean so we are clearly within the “inundation” zone. However, the tsunami would arrive from the north and we are on the south side of Molokai which has 2,000 feet high sea cliffs between us and the north side. But, apparently there is a wrap around effect for the waves and the risk of wave reflection, ie. in our case, the waves could hit Lanai and reflect back to the south side of Molokai. In any case, we needed to heed the evacuation order.

Hawaii has a well articulated plan for coastal evacuation during the threat from tsunami. There are sirens, police vehicles driving the highway with flashing lights and loud speaker announcements and even civil defense planes that fly the coastlines with a siren. Since we have no car we figured that worst case we could leave on foot and go down the road a short distance and turn up any one of several streets which would take us to substantially higher ground very quickly. We know this because we have walked that area on some of our daily walks. Instead we were able to join some of our neighbors who were going to their friend’s house which is located on one of those nearby streets.

The tsunami arrived and resulted in wave heights of up to 2.5 feet above normal sea level in Kahului harbor on the island of Maui. So no harm was done to people or property but Hawaii got an opportunity to test their notification and evacuation process which was last used in March 2011 following the earthquake near Japan. The next day we once again had sunshine and pleasant breezes.